1. Field Of The Invention
This invention relates to a molded plastic closure which includes a sealing liner to permit the closure to be applied in a sealing manner to a liquid containing glass or plastic bottle. More particularly, this invention relates to a compression molded plastic closure with a sealing liner that may be formed in the closure during the compression molding process. The closure is shown both in an embodiment which is suitable for use in applications where the associated container must be sealed both on the top and on the side, for example, in the packaging of carbonated beverages, and in an embodiment where the associated container need be sealed only on the top thereof.
2. Description Of The Prior Art
Lined, compression molded thermoplastic closures are known in the prior art, and have been extensively used in the packaging of carbonated soft drinks, where each such closure must seal the associated container on the top and around an annular portion of the side of the finish of such container. U.S. Pat. No. 4,378,893 (S. L. Wilde, et al.) discloses a type of top and side seal compression molded lined plastic closure which, in a nominal diameter of 28 millimeters, has been utilized successfully in the packaging of carbonated soft drinks. U.S. Pat. No. 4,407,422 (S. L. Wilde, et al.) discloses a similar compression molded lined plastic closure for a bottle. U.S. Pat. Nos. 4,381,840 (E. M. Ostrowsky) and 4,462,502 (W. R. Luenser) illustrate other types of lined, molded plastic closures for bottles.
Each of the aforesaid prior art patents discloses a molded plastic closure that utilizes a sealing liner which extends beyond the sealing surface of the container that the closure is to be affixed to. In such a closure, the periphery of the liner engages and is supported by the inside of the sidewall of the closure or by structure of the closure which is closely adjacent thereto and which is rigidly connected thereto. This construction requires excess material in the liner of the closure and, in the case of a liner which is compression molded within the body of the closure, for example, a compression molded liner of the type disclosed in the aforesaid U.S. Pat. No. 4,378,893, the size of the liner complicates the compression molding process and tooling.